I've build quite a few custom boards using the WS2812B's and ESP8266's and this is my first time building a board that uses the SK6812's and I'm having a bit of an issue. I have a board with 33 SK6812's wired to GPIO 2 of the ESP6812. I'm level shifting Pin 2 of the ESP8266 to output a 5V signal for the data line. Each LED has a Power pin and GND pin going to a Power Plane on the PCB and a .1uF decupling cap on each SK6812. I'm currently powering the board on a lab grade power supply putting our a clean 5VDC and capable of producing more current then my board will ever need.

With that information said only 24 of the 33 SK6812's are working. Looking on a scope I'm getting bits coming out of the DO pin on the 24th LED but the 25th-33rd are not lighting. I've tried the Neo-Pixel strand test code for the RGBW LED's as well thinking it might be a bug in my code but that has the same issue.

I've replaced both the 24th and 25th SK6812 with new ones, replaced the decoupling cap, and swapped out the ESP8266 with different units as well. When I run tests the first 24 RGBW work properly, but 25-33 do not work, using the "RGBWstrandtest.ino" example.

Are there limitations or issues or bugs with the sk6812's or neopixel library that I might not be aware. I'm trying to trouble shoot this and fix it before I build 5 more boards.

I stand corrected. I ended up replaceing 7 sk6812s on the board by hand. A few of them more then once. I must just have a few defective ones in the tape reel i bought or the reflow oven profile wasnt dialed in perfectly. The board is working now but its making me leery of using sk6812's again in future products.